Field of the Invention
The present invention relates to an image forming apparatus configured to convey a stopped sheet to an open portion of a conveyance path.
Description of the Related Art
Image forming apparatus such as a copying machine and a printer are configured to form an image on a recording medium such as a paper sheet (hereinafter referred to as a “sheet”). In each of the image forming apparatus, the sheet is conveyed from a sheet containing portion to a sheet delivery portion through an image forming portion in the inside of the image forming apparatus. When a sheet jam (hereinafter referred to as “jam”) has occurred in the inside of the image forming apparatus, it may be difficult for a user to clear the jam depending on a stop position of the jammed sheet.
FIG. 11A and FIG. 11B are explanatory views of jammed sheets in the inside of an image forming apparatus 100. For example, when a jammed sheet P1 is present at a position immediately after sheet feeding as illustrated in FIG. 11A, most of the leading edge of the jammed sheet P1 is not fed out of a first sheet feed cassette 220. In this case, even when a lower door 260 provided on the side surface of a main body 100a of the image forming apparatus 100 is opened so as to remove the jammed sheet P1, the user's hand is hard to reach the jammed sheet P1, thereby being difficult to clear the jam.
Incidentally, there is generally known a method of conveying, in the event of the jam, the jammed sheet P1 to a position from which the user can easily clear the jam. When the distance between the jammed sheet P1 and a jammed sheet P2 preceding the jammed sheet P1 is short as illustrated in FIG. 11B, however, the jammed sheet P1 cannot be conveyed because the jammed sheet P1 may hit against the preceding jammed sheet P2 when the jammed sheet P1 is conveyed.
Therefore, according to Japanese Patent Application Laid-Open No. 2012-78604, when the lower door 260 is opened, the jammed sheet P1 is forcedly conveyed by an amount set in advance depending on the size, the type, and the like of the jammed sheet P1. FIG. 12A, FIG. 12B, and FIG. 12C are explanatory views of forced conveyance of the jammed sheet P1 in the related art. FIG. 12A is a view for illustrating a state in which the lower door 260 is opened. FIG. 12B is a view for illustrating the jammed sheet P1 forcedly conveyed in a direction indicated by the arrow A. As illustrated in FIG. 12B, the jammed sheet P1 can forcedly be conveyed to an open space defined by the opened lower door 260. Thus, even when an inter-sheet distance between the trailing edge of the preceding jammed sheet P2 and the leading edge of the jammed sheet P1 is short, the leading edge of the jammed sheet P1 can be conveyed to the position from which the user can easily clear the jam.
Depending on the type or stiffness of the sheet, however, the jammed sheet P1 is forcedly conveyed in a direction indicated by the arrow B as illustrated in FIG. 12C, with the result that the jammed sheet P1 may enter a conveyance path of an upper door 261, which is not opened. As in this case, the related art has a problem in that the jammed sheet P1 may be conveyed to a position where it is even more difficult for a user to clear the jam.